Flooring construction



June 20, 1939.

H. S. NAGIN FLOORING CONSTRUCTION 2 Sheets-Sheet l lNVENTOR HarrySBA/(57in Filed May- 18, 1937 ATTORNEYS June 20, 1939. H. s. NAGlNFLOORING CQNSTRUCTION Filed May 18, 1937 2 Sheets-Sheet 2 ttrlzlINVENTOR Harry S.. I m ,M

HTTORNEYS Patented June 20, 1939 UNITED STATES PATENT OFFICE FLOORINGCONSTRUCTION Application May 18, 1937, Serial No. 143,278

12 Claims.

My invention relates to flooring constructions of the type whichdirectly support traffic without the aid of reinforcing filling or acontinuous substructure and is particularly directed to the type offloors which are made from open mesh gratings formed from metalstructural bars.

In certain installations of trafllc-supporting roadways, such as areencountered in bridges, the floor or deck is constructed of open-workgratings or grids which are supported directly on a skeleton supportingstructure such as the sills or stringers of the bridge or likestructure. Such floors are, in general, constructed from sectionalunits, each unit being made of spaced apart bearing bars which span thespace between the stringers or sills, the bearing bars, in turn, be ingsecured together at their tops by transverse cross bars, the tops of the'cross bars and the bearing bars being in the same plane. Frequent- 1y,but not always, the bearing bars are connected adjacent their bottoms bytransverse tensiondistributing members. The gratings present a cell-likestructure to the trallic and this reticuor structural sections.

lated traffic-bearing floor is substantially skidproof and highlywear-resistant. At the same time, it forms a comparatively lightstructure which permits the bridge to be economically designed andfabricated due to the lessened dead load of the floor.

Due to the large area tobe floored in the average bridge, it is commonpractice to manufacture the gratings in unit sections or panels ofconvenient sizes which can be economically fabricatedin the shop fromcommercial length bars These units are assembled in the bridge andjoined together in various ways so as to present a substantiallycontinuous traffic-supporting surface. The structures are usuallydesigned so that the joints occur directly over the sills or stringersof the bridge. Because of the open construction of the floor, no dirt orforeign matter is retained on the surface, 'but passes through thegrating entirely, except where the grating passes over the sills orstringers or other parts of the supporting framework with which thegrating comes in direct'contact. At these points, dirt and refuse ofvarious kinds collect on top of the supporting sills or stringers andabsorb and retain moisture so that corrosion of the bearing bars andadjacent parts of the supporting framework takes place.

One of the objects of my invention is to provide a construction whichwill protect the bearing bars and the sills, stringers or other parts ofthe supporting structure onwhich the bearing bars rest so that refuseand attendant moisture cannot collect on the supporting structure andcome in contact with the various surfaces and cause corrosion.

The joints between the grating units are frequently made by lapping thebearing bars of adjoining units and.this necessitates that theregularity of the' top cross bars be interrupted, thus tending to impairthe regularity and the skid and wear-resistant properties of thetraction surface, so that it is advisable that precautions be takenwhereby the traction surface will not be impaired at and adjacent to thejoints. The lapped bars also present a problem in corrosion as it isimpossible to make a permanently water-tight joint except atconsiderable expense. If water gets between the overlapping bearingbars, they inevitably become rusted and the effective life of theflooring is consequently diminished. I have discovered that the jointscan be protected and the trafllc surface preserved by making the jointso that it will be covered by a plate set into the grating whereby thetop of the floor and the top of the grating will be in the same plane.Such a plate also serves, to prevent the deposition on the stringers orsills directly beneath the joint of road soil and dirt which tends tocollect there and absorb and retain moisture, and thus cause rusting ofthe adjacent parts.

In the accompanying drawings wherein like numerals designate like parts,I have illustrated a present preferred embodiment of my invention. Inthe drawings:

Figure 1 is a view of a joint made according to my invention and alongthe line I--I of Figure 3;

Figure 2 is a cross sectional view along the line II--II of Figure 1;

Figure 3 is a top plan view of 'a part of the structure;

Figure 4 is a perspective view of a detail of the structure;

Figure 5 is a cross sectional view of the intersection of the floor anda part of the supporting structure;

Figure 6 is a perspective view of a detail of Figure 5;

Figure 7 -is a perspective view of another form of my invention;

Figure 8 is a plan view of the same; and

Figure 9 is a perspective view of a detail.

Figures 1 through 4 show a flooring structure consisting of open topgrating units or panels 2 and 3, supported on a sill or other supportingframework 4 of a bridge or like structure. Each rating consists ofspaced apart bearing bars 5,

- bars 5 and 5 may be connected in any suitable manner, as for example,by electric pressure welding. The bearing bars 5 are connected adjacenttheir bottoms by trailic-distributing bars I, although in certaindesigns, these bars can be omitted. The grating units are placed overthe transverse supporting member 4 so that the hearing bars aretransverse thereto and the ends of the bearing bars 5 of the units abut.one another or lap, as desired. They are shown in Figure 3.as abutting.It is customary to weld at least some of the bearing bars to eachsupport where they contact-the support, and in some instances, thebearing bars are welded to one another so as to form asubstantiallycontinuous floor or deck.

On each side of each of the sills 4, a form plate 8 is placed so as tobe in close contact with the sill 4 and to extend upwardly between thebearing bars 5 to a position substantially flush with the top of thegrating. .I prefer to make the form plate 8 of thingauge metal in theshape of rectangular plates having slots 9 equal in width to the widthof the bearing bars. The slots 9-are spaced apart a distance equal tothe spacing apart of the bearing bars and are of a width and depthsubstantially equal to the width and depth of the bearing bars so thatwhen the plate is placed in position on each side of the sill, as shownin Figure l, a space is partitioned oflf above the sill, which space isfilledwith a suitable substantially waterproof substance I0, such ascementitious material or a plastic mass,- as the case may be. Such afilling'is hereinafter referred to as a filler.

In Figure '4, I have shown the form plate 8 as a rectangular sheetslightly wider than the depth of the slots, The sheet is of convenientlength for handling and assembling. Again, the form plate may beangularly shaped, as shown in Figure 6, which has a base portion II andan upright portion 12, in which upright portion the slots l3, shaped andsized similarly to the slots 9 shown in Figure 4, are located. The formplates made according to Figure 4 are placed in position in contactwiththe edges of the sill flanges as shown in Figure 1, and may besecured in position as by welding or friction. Form plates madeaccording to Figure 6 are placed in position on the sill 4, asillustrated in Figure 5, in which construction, the base portion llextends beneath thebearing bars 5', while the upright portion extendsupwardly alongside the bearing bars and provides the form against whichthe filler I II is placed.- It is'obvious that, the form plates canbemade of any suitable material and of any suitable length and mayextend merely between two adjacent bearing bars, if so desired. The formplates oithe desired type may be secured in 'position by friction or inany other suitable manner,

such as by spot welding. The plates may be' positioned at thefabricating plant or placed in position in the field as circumstancesdictate, and may be removed when the filling material has been set ormay be left in position.

' It is evident that the construction I have described and illustratedin both Figures 1 and 5 may be used where/the sill floor comes directlyunder a joint, as shown in Figure 1 or where the sill is intermediate ofthe grating unit,; as shown in Figure 5.

This construction provides complete protection for the sill and adjacentpartsof the bearing bars and'insures that the anti-slip qualities willnot be impaired atthe joints and-the strength of the flooring at thejoints will not be decreased.

Figures 7 through 9 show a construction of a suitable joint for use inflooring made according to my invention. In these figures, I have shownthe bearing bars 5 as overlapping one another at the joints. Each jointis placed over a suitable sill or other supporting portion of theframework 4. The ends of the bearing bars are notched from the top, asshown'in Figure 9, and for a distance such that when the grating unitsare placed in position, the notched space ll will accommodate a fillerplate l5 which is somewhat wider than the top of sill 4. The fillerplate i5 is the same in thickness as the depth of the notch l4 so thatthe topof the filler plate 15 is flush with the top of the adjoininggratings 2 and i. I prefer to make the filler plate l5 with a suitableanti-skid surface which may be formed either by projections extendingabove the mainbody of the plate or depressions in the main body of theplate; or again, theplate may have 'an abrasive top surface so as topresent adequate anti-skid and traction properties. If preferred, thefiller plate .l5 may be of foraminous construction, in which case careshould be taken that the holes do not appear in the finished structuredirectly above the bearing bar overlapping joints. The bearing bars maybe secured to one another by edge welding the end portions l6, as shownin Figure 2, or if desired, an expansion joint may be provided, in whichcase, suitable slotted holes I! should be provided in the ends of thebearing bars. Appropriate bolts or rods l8 may extend through the holes11.

By the use of a form plate in the construction illustrated in Figures 7through 9, the end portions of the bearing bars are protected fromdirect impingement of dirt and moisture which would tend to rust thebars, especially at the joints. The filler plate also serves to preventdust from gathering on the sill flange beneath, which dust will absorband retain moisture and tend to corrode the bearing bars and the sills.In certain constructions, the ends of the bearing bars are preventedfrom tilting up and interfering with trafllc.

It is customary to place the grating units or panels in a bridge or likestructure in such a manner that the main bearer bars 5 run transverselyof the direction of travel, in which case the filler l and filler platel run parallel to the direction of tramc and serve as-a markerorstrlp toguide the trafllc. If desired, the filler or filler plate may be coloredso as to form a contrast to the surface presented by the rest of theunit or panel. Whether definitely colored or not, the continuous surfaceoverlying the supports 4 is visually quite different from thereticulated surface presented by the rest of the unit.

The filler also serves a further important function when galvanized orcoated units are employed. It is customary to secure .the bearer bars 5to the supports 4 by welding. The finished weld presents an uncoated,metal surface and this surface, as well as adjoining surfaces thecoating of which has been destroyed by the welding, are readily attackedby rust. The filler it entirely covers thesewelded surfaces andefiectively prevents rusting thereof.

While I have illustrated and described the preferred embodiments of myinvention, it will be understood that the same is not limited thereto,but may be otherwise embodied and practiced within the scope of thefollowing claims.

I claim:v

1, In a flooring structure of the class described, an open type gratingunit, a support therefor, and a filler over the support and extendingfrom the support upwardly to the topsurface of the grating unit, therest of the unit being unfilled.

' 2. In a flooring structure of the class described, an open typegrating having spaced apart parallel bearing bars resting on a support,and a substantially water-proof material filling the spaces between thebearing bars above the support from the support to the top of thebearing bars, the remainder of the said structure being open.

3. In a flooring construction of the class described, a gratingcomprising a plurality of metal strips all set on edge with their upperedge surfaces all lying in the same plane and their lower edgessupported on transverse supporting members, said strips being heldtogether at points of contact one with another with sufiicient rigidityto form a unitary structure presenting a reticulated upper surfaceserving as a roadway, said grating being filled above the transversesupporting members only with a filler.

4. In .a flooring construction of the class described, a gratingcomprising a plurality of metal strips all set on edge with their upperedge surfaces all lying in the same plane and their lower edgessupported on transverse supporting members, said strips being heldtogether at points of contact one with another with sufficient rigidityto form a unitary structure presenting a reticulated upper surfaceserving as a roadway, form plates extending upwardly from the sides ofthe transverse supporting members and between the bearing bars, and afiller in the space over the transverse supporting members and betweenthe form plates.

5. In a flooring construction of the class described, a gratingcomprising a. plurality of metal strips all set on edgewith their upperedge surfaces all lying in the same plane and their lower edgessupported on transverse supporting members, said strips being heldtogether at points of contact one with another with sumcient rigidity toform a uni-- tary structure presenting a reticulated upper surfaceserving as a roadway, form plates extending upwardlyfrom the sides ofthe transverse supporting members and between the .bearing bars, saidform plates having a portion thereof in contact with the top of thetransverse supporting member, and a filler in the space over thetransverse supporting members and between the form plates.

6. A floor structure comprising a succession of grating panels, onepanel interfitting with the next, the interfitting end portions of thepanels being of reduced thickness to provide a transverse recess vin thefloor where the panels join, and a metal plate in the recess, the top ofthe metal plate being flush with the surface, of the grating.

7. A floor structure comprising a succession of grating panels joiningone another, said panels having bearing bars which interfit with thebearing bars of adjacent units at the. joint,- the interfitting endportions of the bars being of reduced thickness to provide a transversenotch in each panel where the panels join, and means in the slot toprotect the interfitting ends of the bars, the top of said means beingflush with the top surface of the panels.

8. A floor structure comprising a succession-of grating panels, onepanel being joined to the next, the adjoining end portions of the panelsbeing of reduced thickness to provide a transverse recess in the floorwhere the panels join, a metal plate in the recess, the top of the metalplate being flush with the surface of the grating, and a transversesupporting member under the adjoining panel ends, said plate having awidth at least co-extensive with the width of the support to protect thegrating where it rests on the support from accumulating debris.

9. A floor structure comprising transverse supporting members, opengratings on the supporting members providing an open reticulatedtraflicbearing floor, and means flush with the top surface of thegrating over the supporting members only of a width substantiallyco-extensive with the width of the supporting members for excluding theaccumulation of debris in the grating where the gratings rest on thesupporting members, the gratings being otherwise open. 10. In a flooringstructure of the class described, an open type grating unit, a supporttherefor, and means, the upper portions of which are in substantiallythe same plane as the top ofthe unit and extending longitudinally of thesupport and for a sufficient distance therealong to protectsubstantially all the contacting portions of the grating and thesupport.

11. In a flooring structure of the class described, an open type gratingunit, a support therefor, and means, the upper portions of which are insubstantially the same plane as the top of the unit and extendinglongitudinally of the support and substantially the same width as thewidth of the support for protecting substantially all the contactingportions of the grating and the support. I

12. In a flooring structure of the class described, an open type gratingunit, a support on which said unit rests and means for excludingaccumulation of foreign, matter on the support in those cells of thegrating which are over the my 8. mom.

